When the Skies Turn Dark

Why we love it

See hundreds of tornado warnings together with geography and seasonality—and sense the terror of weather phenomenon! We love that this map shows how some warnings create a quilt-like pattern across county lines, and others are uniquely shaped to a specific storm. As you click on the map, notice certain locations have dozens of warnings while others, just a few miles away, have almost none. Such is the randomness of these storms.

Why it works

This map works by giving insight into something reckless and frightening. The top tabs show how time of year affects storm location and frequency. Notice that the further into the future a warning is aimed, the less certain we can be of where the tornado will land. Many warnings are cone-shaped and wider at one end. Interestingly, most cone-shaped warnings trend from southwest to northeast due to humid hot air from the south colliding with dry air from the west.

Important steps

Pick a symbol to show each warning

When working in ArcGIS Online, use smart mapping and pick “single symbol” to show each warning as a solid coloured box.